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Recommendations for clinical research in children presenting to primary care out-of-hours services: a randomised
Anouk Ah Weghorst1, Gea A Holtman1, Pien I Wolters1
1Department of General Practice and Elderly Care Medicine, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.
Insights
Informed consent and off-protocol prescribing in pediatric trials impact inclusion rates but not participant selection. A parallel cohort study can help assess selection bias in pragmatic trials.
Area of Science:
- Pediatric research
- Clinical trial methodology
- Primary care research
Background:
- Recruiting children in primary care for research is challenging and can introduce selection bias.
- Informed consent procedures, especially in acute settings, can affect study feasibility.
- Off-protocol intervention use is common in pragmatic randomized controlled trials (RCTs) in primary care.
Purpose of the Study:
- To evaluate how informed consent procedures influence study inclusion in a pediatric RCT.
- To assess the impact of off-protocol medication prescribing on participant selection in a pediatric RCT.
Main Methods:
- A pragmatic RCT and a parallel cohort study were conducted.
- The study focused on children aged 6 months to 6 years with acute gastroenteritis (AGE) in primary care out-of-hours services.
- Feasibility of informed consent, off-protocol ondansetron use, and inclusion/exclusion criteria were assessed.
Main Results:
- The informed consent process reduced RCT feasibility, with 39% of children having only one parent present.
- Oral ondansetron was prescribed off-protocol to 4.1% of children, with 19 eligible for the RCT.
- Children in the parallel cohort study had fewer dehydration risk factors than RCT participants, despite similar GP assessments.
Conclusions:
- Informed consent and off-protocol medication use affect inclusion rates but have minimal impact on selection bias.
- Parallel cohort studies can aid in evaluating selection bias in RCTs.
- Pilot studies are valuable for identifying potential barriers to participant inclusion.
Background:
Research in primary care is essential, but recruiting children in this setting can be complex and may cause selection bias. Challenges surrounding informed consent, particularly in an acute clinical setting, can undermine feasibility. The off-protocol use of an intervention nearing implementation has become common in pragmatic randomised controlled trials (RCTs) set in primary care.
Aim:
To describe how the informed consent procedure affects study inclusion and to assess how off-protocol medication prescribing affects participant selection in a paediatric RCT.
Design & Setting:
A pragmatic RCT evaluating the cost-effectiveness of oral ondansetron in children diagnosed with acute gastroenteritis (AGE) in primary care out-of-hours services and a parallel cohort study.
Method:
Consecutive children aged 6 months to 6 years attending primary care out-of-hours services with AGE were evaluated to assess the feasibility of obtaining informed consent, the off-protocol use of ondansetron, and other inclusion and exclusion criteria.
Results:
The RCT's feasibility was reduced by the informed consent procedure because 39.0% (n = 325/834) of children were accompanied by only one parent. GPs prescribed ondansetron off-protocol to 34 children (4.1%) of which 19 children were eligible for the RCT. RCT-eligible children included in the parallel cohort study had fewer risk factors for dehydration than children in the RCT despite similar dehydration assessments by GPs.
Conclusion:
The informed consent procedure and off-protocol use of study medication affect the inclusion rate, but had little effect on selection. A parallel cohort study alongside the RCT can help evaluate selection bias, and a pilot study can reveal potential barriers to inclusion.
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